Not able to merge surfaces into solid. Can somebody help?

I am a new user of Solidworks. So any help you offer will be of great service and regarded very highly.
I am facing trouble trying to merge different surfaces (with minor gaps) into a solid. I tried many different methods out there on various websites, forums, tutorials, etc... but, so far, have had no luck. Can anybody please help??? Please can anybody tell me what am I doing wrong here? I know, for once, that there are a lot of knitted surfaces that I've created. Please guide me on how to go about reducing the redundant ones.
I've attached the part file here.

Thankyou in advance.

6 Answers

I just found out you have also 4 solids in the model. You will not be able to merge the solid with the surfaces untill all the Surfaces are merged and converted into solid.

There are also duplicate surfaces (part of the Surface that overlaps with another one). Which also Needs to be takes care of before merging the surfaces.
Attached is one of many examples that i found in your model.

Here you go.
Your surfaces are too sharpp at some Points. That makes the lofting Feature complicated.
Your model is also not symmetric (have a top view).

Still I tried my best to merge them all into one Surface and solid.

How did u manage to create a single loft here? I tried real hard to do it earlier, but it just didn't budge. Request you to please provide few steps that you took, if possible. I would be greatly thankful.

The answer is lying in the model tree of the part.
I took help of 2 3d sketches for Profile and a 3d sketch for guiding. Without the guide sketch the Surface twists without any control.

@Sahedul: When I am trying to edit something (which has many parent-child relations) in your version of the file, SW2015 simply crashes. Any idea why this may be?